Death Master File

The Death Master File (DMF) is a computer database file made available by the United States Social Security Administration since 1980. It is known commercially as the Social Security Death Index (SSDI). The file contains information about persons who had Social Security numbers and whose deaths were reported to the Social Security Administration from 1962 to the present; or persons who died before 1962, but whose Social Security accounts were still active in 1962. As of 2018, the file contained information on 111 million deaths.

In 2011, some records were removed from the file. Specifically, ZIP Code information (last known residence and last benefit payment address) was stripped due to identity theft concerns. Public updates to the Social Security Death Index ceased entirely in 2014. Since that time, access to newly reported deaths has been restricted to approved entities through the Limited Access DMF system, which requires certification under U.S. Department of Commerce regulations (15 C.F.R. Part 1110).